The present invention relates to the field of golf club design. Specifically, the invention us directed to an improved xe2x80x9ciron-stylexe2x80x9d golf club head having multiple face inserts pressed into an open face pocket.
Over the recent years, golf clubs have undergone significant design improvements. Perhaps the most significant improvement in golf club design has been the introduction of perimeter weighting to both iron-style and wood-style club heads. Perimeter weighting encompasses the removal of metal from central portions of a clubhead and the redistribution thereof to the perimeter of the head. This results in an expansion of the xe2x80x9csweet spotxe2x80x9d of the clubface. When a golf ball is struck by a club substantially at its sweet spot, the golf ball will experience its optimal trajectory and distance. While great advances have been made in weighting technology of club heads themselves, the removal and redistribution of mass in club heads has affected the swing weight of many perimeter weighted clubs.
The typical teachings in the art today prefer softer alloy iron-style clubs, where club xe2x80x9cfeelxe2x80x9d is considered of paramount importance. In fact most touring professional golfers still use forged, blade-style irons, which are made of steel alloys that provide optimum club feel. Unfortunately, the average golfer does not possess the skill to truly xe2x80x9cfeelxe2x80x9d the difference when his or her club strikes a golf ball at different positions on the club face, let alone control the same.
The individual golf clubheads in a set typically increase progressively in strike face surface area and weight as the clubs progress from the long irons to the short irons. Therefore, the clubheads of the long irons have a smaller strike face surface area than the short irons and are typically more difficult for the average golfer to hit consistently well. For conventional clubheads, this arises at least in part due to the smaller sweet spot of the corresponding smaller strike face.
To help the average golfer consistently hit the sweet spot of a club head, many golf clubs are available having heads with so-called cavity back designs with increased perimeter weighting. Another more recent trend has been to simply increase the overall size of the clubheads, especially in the long irons. Each of these features will increase the size of the sweet spot and therefore make it more likely that a shot hit slightly off the center of gravity of the club head still makes contact with the sweet spot and flies farther and straighter as a result. One challenge for the golf club designer when maximizing the size of the clubhead concerns maintaining a desirable and effective overall weight of the golf club. For example, if the clubhead of a three iron is increased in size and weight, the club may become difficult for the average golfer to properly swing.
Another problem area for the average golfer is that of excess vibration resulting from an off center impact with the golf ball. Various types of vibration dampeners have been incorporated into clubheads to absorb these impact vibrations. However, there is still need for improvement in both the area of weight redistribution and vibration dampening in golf club heads, especially oversize iron type club heads.
The disclosed invention is an improved, iron-style golf club, which comprises a clubhead having a front portion in which a cavity is defined therein. Interposed within the cavity are a plurality of inserts. A strike face insert which is preferably made of stainless steel is backed by a dampening insert that is preferably backed by a light weight back insert. Preferably, the dampening insert has a specific gravity greater than the face insert and the light weight insert has a specific gravity less than the face insert. Preferably the dampening material has a tensile modulus that is less than the face insert and the light weight material has a tensile modulus that is greater than the face insert.
The dampening insert is preferably formed of soft lead to significantly soften the xe2x80x9cfeelxe2x80x9d of the iron. The high density of lead alloy also brings the head back up to the required head weight. Other suitable dampening materials include tungsten filled polymers.
The thickness of the heavy dampening material can be varied in combination with the insert to achieve various head weight requirements. By increasing the thickness of the dampening insert and decreasing the thickness of the light weight insert, it is possible to increase the head weight without any change in the cavity volume.
Preferably, the dampening material is very moldable under pressure, so that it fills all the void regions behind the face and between the body. The light weight insert on the back supports the dampening material and prevents it from squeezing out.
The position and amount of the heavier weighted material can be altered in relation to the club face. Therein, the specific gravity of the iron head will be, at the lowest point for long irons (such as a two iron), and will rise incrementally as the irons get shorter.
These and still other objects of the disclosed invention will become apparent from the following description.